The present invention relates to a bridging span structure intended in particular for the clearing of ditches by vehicles such as armoured vehicles of the Engineering Corps and a system for the transport on a vehicle of at least two bridging span structures intended for the clearing of ditches and for laying down the bridging span structures over the ditches from the vehicle.
A system has been proposed for laying down from a vehicle a bridging span of short length or of greater length after the end-to-end assembly of two or more bridging spans of short length.
Such a system is described in the document FR-B-2,683,837 in the name of the applicant and essentially comprises a beam for supporting and launching a bridging span or assembled bridging spans, displaceable in relation to the vehicle towards an overhanging position; means for the displacement of the bridging span or of the assembled bridging spans in relation to the beam to an overhanging position forward of the beam; and a plate supporting in a guided manner the beam and which may tilt in relation to the vehicle together with the beam to permit the laying down of the bridging span or of the assembled bridging spans over a ditch to be cleared.
In the inactive position or position of transport on the load vehicle, the beam has its portion behind the supporting plate accommodated between two superposed bridging spans and the connecting arms forming braces of both bridging spans, each one being U-shaped and pivotally connected at its ends to two internal side-walls, respectively, of two central boxes of two bridging span elements. Both connecting arms of the lower bridging span assume a downward swung or lowered position permitting to increase the space for the accommodation of the beam and these connecting arms may be simultaneously swung upwards by a lifting table to a position substantially parallel to the frame of the vehicle, in which they are locked to the lower bridging span.
The hereabove known system has thus the major inconvenience to require a complex structure of lifting table mounted onto the chassis of the vehicle and associated control means for raising it from an inoperative position, after withdrawal of the beam from above the lower bridging span and acting upon the lower ends of the U-shaped connecting arms of this bridging span to move them away from each other to their position of locking to the lower bridging span.